It is common practice to weld and particularly arc weld parts of a metal structure together in a preselected pattern to produce a welded product. An example of this is in tube and header heat exchangers such as automotive radiators where the ends of spaced tubes are welded in certain instances to oppositely spaced header plates. An example of such a welded construction is shown in U.S. Pat. No. 4,159,034 assigned to the assignee hereof.
The present invention provides an apparatus for automatically magnetic arc welding metal pieces such as the ends of spaced tubes to tube receiving flanges in the header plate in preselected sequence and preselected pattern.
One of the features of this invention therefore is to provide such an arc welding apparatus.
Another feature of the invention is to provide such an apparatus which includes means for automatically bathing the electrode and the parts being welded in an inert non-oxidizing gas during the welding process.
Prior art patents discovered in a patentability search before preparing this application are U.S. Pat. Nos. 1,854,536; 1,949,251; 2,602,869; 2,743,342; 2,763,755; 2,803,739; 2,817,001; 2,845,523; 3,294,954; 3,519,785; 3,519,786; 3,560,701; 3,641,309 and 4,056,705. The most important patents of this group appear to be U.S. Pat. Nos. 2,817,001; 3,519,785 and 3,519,786.